"I hope these guys get thrown in jail — they’ll never do it again," Trump said on Saturday. "It’ll destroy their record, they’ll have to explain to mom and dad why they have a police record and why they can’t get a job. And you know what? I’m going to start pressing charges against these people."

"I don’t want to ruin people’s lives. But the only way we’re going to stop this craziness is if we press charges," he added.

Kansas City Police Chief Darryl Forté said on Twitter "most in downtown area lawfully expressed themselves while lawfully assembling." He said a "fogger" was used on two large groups "preparing to fight."

Though Trump claimed he spoke to police and "they said why don’t you cancel," the police chief said later that he was "not aware of any discussion about cancelling the event."

It was after Trump cancelled an event in Chicago on Friday over what he said were security concerns that chaotic scenes broke out, with scuffles and fistfights inside and outside the University of Illinois at Chicago Pavilion.

Those issues were amplified in recent days after video emerged of a man at a Trump rally sucker-punching a protester leaving an event in North Carolina and after a Breitbart reporter accused Trump's campaign manager grabbing her hard enough to cause a bruise. The campaign manager has denied the claim.

Trump himself has said he would like to punch a protester in the face and see another taken out on a stretcher.

On Saturday, he urged security to treat protesters "gently."

"See, I’m a non violent person, did you know that about me?" he told the crowd and dismissed the protesters inside the theater as supporters of Sanders, the Democratic presidential hopeful.